Carton folding machines



June 12, 1962 J. G. GAGE 3,038,388

CARTON FOLDING MACHINES 8 58 11 //v v/v r01? 84/ 84 4/? c K Gus TA was6/7 GE flTTOR/VEYS 5 Sheets-Sheet 3 Filed April 25, 1960 Jack GUS7797003 6 465 HTTOR/VE VS June 12, 1962 J. G. GAGE 3,038,388

CARTON FOLDING MACHINES Filed April 25, 1960 5 Sheets-Sheet 4 //V V570/! (/1961! Gusm mas GAG-E w fgdyyw June 12, 1962 J. a. GAGE CARTONFOLDING MACHINES 5 Sheets-Sheet 5 Filed April 25, 1960 {Vilma I II.

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This invention relates to carton folding machines of the die-plungertype for converting carton blanks into carton form.

By a die-plunger type of carton folding machine is to be understood amachine comprising a generally rectangular sectioned plunger blockwhich, in use of the machine, is forced through a correspondingly shapeddie to erect a carton blank, the side forming portions of the blankbeing upfolded by the die as the blank i forced through the die by theplunger block, the carton being erected or partly erected about theblock.

Depending on the size of the cartons to be erected, so must the size ofthe plunger block and the die be chosen, and one object of the presentinvention is the provision of a carton folding machine of thedie-plunger type having an inter-changeable die and plunger blockwhereby the machine may be readily adapted to fold different sizes ofcartons, simply by inter-changing the plunger block and the die.

There are various known forms of carton which may be folded in a machineof the die-plunger type, and a further object of the present inventionis the. provision of such a machine which may be readily adapted for theerection of cartons not only of different sizes but also of differentstyles.

There is hereinafter described a die-plunger type of carton foldingmachine according to the invention adapted for erecting cartons of thekind some times referred to as roll-over lock cartons.

A carton of this kind has two opposite side or end forming portions withextended or rllover panels at their top edge which are folded over intothe carton into locking engagement with the bottom of the carton to holdthe sides and ends of the carton erect.

A die-plunger type of machine for erecting roll over lock cartonsusually comprises jaw means on the die for gripping the carton after itssides and ends have been upfolded by the die as the carton blank isforced into the die by the plunger so that on withdrawal of the plungerblock the carton is stripped olf the plunger block and supported in thedie aperture, and folding means, for example fingers mounted in recessesin the die walls, and movable from a retracted position, in therecesses, into the die aperture to engage and fold the roll-over panelsinto their locking position.

A further object of the invention is to provide a dicplunger type ofcarton folding machine for folding cartons having one or more roll-overlock panels and having improved mechanism for operating the foldingmeans.

More particularly this object is directed to providing a machine inwhich the folding means is intermittently operated by movement of theplunger assembly over part only of its withdrawal stroke to fold theroll-over lock panel or panels into their locking position, and over acorresponding part of its advancing stroke to retract the folding means.

With an intermittently operated folding means as above described, thestroke of the plunger assembly may be altered within predeterminedlimits to adapt the machine for operation with different dies andplunger blocks suitable for erecting roll-over lock cartons of differentsizes tates tt and requiring different stroke lengths of the plungerassembly to effect the folding operation.

A still further object of this invention is to provide a die-plungertype of carton forming machine having a control system which ensuresthat once a carton folding cycle of the machine has been initiated bythe operator, the operation of the machine cannot be interrupted by theoperator until the cycle has been completed.

The die-plunger machine which will now be described, merely by way ofexample, and with reference to the accompanying drawings, meets all theabove discussed objects in a manner which will be clearly explained.

in the drawings:

FIG. 1 is a front elevation of the machine with the die in section,

FIG. 2 is a side elevation of the machine again with the die in section,

FIG. 3 is a rear elevation of the machine with part broken away to showcertain details of construction,

FIG. 4 shows a detail in side view,

FIG. 5 is a circuit diagram, and

FIG. 6 shows a carton blank which may be erected in the machine shown inFIGS. 1 to 4.

The machine comprises a frame consisting of a pair of vertical, castside panels 16 connected towards the bottom by transverse rods 11 and atthe top by a bell casting 12, and a half cylindrical column 13 mountedcentrally on top of the bell casting.

The bell casting has rebated opening 14 which normally receives aninspection plate (not shown), and a pair of transversely arrangedsupporting webs 15 one to each side, the webs lying approximately in themid transverse plane of the machine.

The column 13 which is hollow has a circular base plate 16 and asemi-circular transverse web 17 spaced upwardly from the base plate 16by about one quarter the height of the column. A front plate 19 normallycloses the open side of the column but is removed in FIG. 1 to show theinternal arrangements in the column.

The top of the column is closed except for a circular aperture in whichis supported switch means in the form of an air valve 26 later referredto.

The column supports a reciprocable assembly generally indicated at 21and comprising a pair of rods 22 slidable up and down in bearings 23 and24 in the web 17 and the base plate 16 respectively, the lower ends ofthe rods being connected to a cam block 25 within the bell casting, andthe upper ends of the rods being connected together by a U-shaped strap26.

Within the column 13 and between the rods 22 is mounted a double actingpneumatic motor 28 comprising a piston and cylinder assembly. The motoris supported from the base plate 16, and the piston rod 29 is connectedto the cam block 25 as at 30 so that as the motor is driven the assembly21 is reciprocated.

A pair of stop sleeves 32, 33 are associated with each rod 22 to limitthe stroke of the assembly 21, the lower sleeves 33 being in the form ofcups supporting rubber bush inserts which act as buffers for the sleeves32, and being themselves supported on further sleeves 33a on the rods22.

The rods 22 slide through felt lined top-hat sectioned members 35clamped against the base plate 16 of the column, the felt beingimpregnated with lubricant to lubricate the rods.

The web 17 carries a further air valve 37 behind the cylinder 28, andthe strap 26 carries a pair of oppositely directed valve lifters 38 and39 one for the valve 20 and the other for the valve 37. The function ofthe valves 20 and 37 and the valve lifters 38 and 39 will hereinafter bedescribed.

Removably attached to the lower face of the cam block 25, by means ofbolts 4% (see also FIG. 4), is a plunger block 41 or generallyrectangular section and having a fiat botom face 45 and having formedtherein, on the front and rear faces, a pair of spread vertical slots 48to avoid interference on the withdrawal stroke of the plunger betweenthe plunger block and certain members later to be described.

The plunger block 41 is vertically movable into and through a diegenerally indicated at 51, the die being removably supported on theframe of the machine. The die is of laminated wood construction and ispartially encased in a metal frame 51a.

In the present example the bottom of the die is flush with the loweredge of the metal frame, but it is to be understood that with a deeperdie, the die may project below the lower edge of the frame 51a, or witha shallower die may not reach as far as the lower edge of the frame.

The side panels '10 carry packing panels 52, conveniently of laminatedwood, which in turn carry runners 53 upon which rests the frame 51a, theframe being slidable on the runners in the manner of a drawer.

To position the die with the die aperture squarely beneath the plungerblock and to fix the die to the frame, knob-headed screws 55 areprovided which pass through the side panels the packing panels 52 andpenetrate into the die side walls, two screws 55 being provided on eachside.

The die comprises a rear wall 60, a front wall 61 and a pair of sidewalls 62. The die walls bound the die aperture which is slightly largerin size than the plunger block.

Before the plun er is operated as hereinafter explained, to move throughthe die on its advancing stroke, a carton blank as shown in FIGURE 6, isslid forward across the surface of a feed-in tray 63' and beneath thelower edge of a transparent guard plate 64 to a location over the die.

The carton blank as shown in FIG. 6 is typical of the roll-over sidelock kind and comprises a bottom panel 66 which substantially coincidesin shape and extent to the bottom face 45 of the plunger block, frontand rear panels 67 and 68 connected along score lines to the long sidesof the bottom panel 66, and end panels 69 connected along score lines tothe short sides of the bottom panel.

The front and rear panels each have at their side edges a pair oflaterally extending retaining flaps 70', connected thereto along scorelines, and the end panels have extended or roll-over panels 71 at theirtop edge again connected along score lines, the roll-over panels 71being themselves scored widthwise to form retaining flaps 72 for thepanels which in the erected carton lie fiat against the bottom panel 66to hold the roll-over panels in position.

To erect the carton from the blank, in the sequence adopted by themachine as will later appear, the flaps 70 are bent upwardly at rightangles to the front and rear panels, and the front and rear panels arethen upfolded through 90 so that the flaps 70 extend inwardly across theends of the carton. The side panels 71 are then upfolded through 90 soas to lie against the tabs 70, and the roll-over panels 71 then foldedin so as to lie against the other side of the flaps 70 from the endpanels with their retaining flaps 72 bent round and lying flat on thebottom panel.

instead of the retaining flaps 72, the roll-over panels may have tongueswhich engage the slots in the bottom panel.

Again, where the flaps 72 are square they may be connected also with theend panels and creased at 45 so as to fold inwardly in the manner ofgussets when the front, rear and end panels are upfolded through 90.

The blank is of a width which fits between guide rails extending alongopposite sides of the tray 63 and is pushed in until the top edge of therear panel comes up against a stop wall 75 at the back of the die.

The bottom panel 66 is then arranged to be squarely over the dieaperture.

As the plunger block is urged downwardly it engages with the bottompanel 66 and forces the blank into the die.

The fiaps 76 are first folded up by the die shoulders '78 and then thefront and rear panels by the shoulders 7? which are below the level ofthe shoulders 78. The end panels are then folded up by the shoulders 56of the die, the carton then being partially erected about the plungerblock.

Mounted on pivots 81 in recesses 82 in the front and rear walls 61 and6d of the die are four jaw members 33, a pair in each wall. The jammembers are pivoted at their upper ends and may be swung on their pivotsto retract then fully into the die walls. The jaw members are urged to aprojected position as shown in FIG. 2 each by a coiled compressionspring 84 In the projected position each pair of jaw members engages astop bar 85, the jaw members having camming surfaces 86 which then liein the path of movement of the bottom panel of the carton backed by theplunger. The camming surfaces 86 each terminate in an overhanging lip -7which has an interfacing lip 38 formed at the lower end of the jaw bar.The lips 87 and 88 form the jaws proper and are spaced vertically by anamount equal to the height of the carton front and rear walls.

As the plunger block descends through the die with the partially formedcarton thereabout the bottom panel engages the camming surfaces 86 andpushes the jaw members back into the recesses 82. When the top edges ofthe front and rear panels of the carton clear the edges of the lips 87the jaw bars are pushed out by the springs 84 so that the lower lips 88engage under the bottom panel of the carton and the top lips 87 engageover the top edges of the front and rear panels.

At this instant the plunger reaches the end of its advancing stroke andcommences to withdraw.

The slots 43 in the plunger block align with the jaw members and allowthe block to move upwardly past the projecting lips 87. This actionstrips the carton from the plunger the carton being retained by the lips87 resting on the lips 83.

The final folding operation of the roll-over panels 71 is now ready tobe undertaken.

Mounted on spindles 9-3? and in recesses 91 in the die walls 62 arefingers %3. By rotating the spindles, the fingers may be swung roundfrom a retracted position, as shown in chain dotted line, to engage andfold inwardly the roll-over panels. The tips of the fingers engage theroll-over panels on the crease line of the flaps '72 so that as theflaps come against the bottom panel the flaps are folded relatively tothe roll-over panels proper and the crease lines are tucked right intothe angles between the bottom panel and the end panels of the carton.

The spindles are journalled in the die walls 62 and extend from the dieto the back of the machine frame where they are journalled, in addition,in holes in a transverse metal strap 95 removably attached to the rearedges of the side panels 16 of the frame of the machine. Each spindlecarries a sprocket wheel 94 which is driven by a chain from a diagonallyopposite one of a further pair of sprocket wheels 96 on spindles 97journalled in the rear wall of the bell casting 12 and in the webs 15.

A further strap 93 extends across the back of the machine above thestrap 95 and is likewise removably attached to the rear edges of theside panels 10. The strap 98 carries a chain tensioner 99 which isadjustable up and down by virtue of its fixing slot 99a to alter thetension in the chains.

At their inner ends the spindles 97 each carry a trigger lever having acam follower in the form of a roller ltil to coact with a cam track 102in the cam block 25.

In the position shown in FIG. 1 the plunger has just reached the end ofits withdrawal stroke and it will be seen that the fingers 93 have beenswung round into their position fully folding the roll-over panels ofthe carton resting on the lips 88. The precise manner in which thisfolding operation is achieved will later appear.

The machine is now ready to erect the next carton the blank of which isslid in over the die aperture as before.

As the plunger is again urged downwardly, over an initial part of itsadvancing stroke, the levers 100 are swung round by the interaction ofthe cam track 2 on the rollers 101 until the rollers emerge from theopen ends 103 of the cam track. The angular movement imparted to thelevers, which in the present example is in the order of 120 istransmitted to the sprocket wheels 96 which in turn drive the sprocketWheels 94. The sprocket wheels 96, 94 are geared up so that the greaterangular movement of 180 required to retract the fingers 93 into theirrecesses is achieved.

Upon the further downward movement of the plunger the rollers 161 run onthe rods 22, the rollers being urged into engagement with the rods bysprings 105 connecte between the levers 100 and the bell housing 12.

The bottom panel of neXt carton formed partially about the plunger blockengages the camming surfaces 86 and pushes the jaw members back into therecesses 82 thereby releasing the previous carton for ejection throughthe bottom of the die by the next carton as it is pushed by the plungerblock into position between the lips 87 and 88 of the jaw members.

On the subsequent withdrawal stroke of the plunger the newly, partiallyformed carton is stripped from the plunger block as previouslydescribed.

The rollers 101 continue to run on the rods 22 until the plungerapproaches a terminal part of its withdrawal stroke when the rollers 101enter the open ends 133 of the cam track 102 and the levers 1% are swunground by the interaction of the cam track on the rollers whereby thelevers are returned to their position shown in FIG. 1 and the fingers 93are swung out to fold the rollover panels of the newly formed carton nowsupported on the lips 88 of the jaw members.

From the foregoing it will be seen that the folding means i.e. thefingers 93 are intermittently operated by the movement of the plungerand over corresponding parts of the advancing and withdrawal strokes ofthe plunger, there being a considerable amount of lost motion as therollers 1121 traverse the length of the rods 22.

This results in a rapid and therefore improved folding action of theroll-over panels.

FIG. 5 shows diagrammatically the control system for the machine andthis control system will now be described.

A manual switch 110 which, in the present example is a foot operated airvalve, controls the supply of compressed air through a pipe 111 to oneside of the air valve previously referred to. The other side of thevalve 20 communicates through a pipe 112 with one side of an air relayvalve generally indicated at 113. The relay Valve comprises a spool 114having four lands 115, 116, 117 and 118 defining in the valve casing 119three annular chambers 120, 121 and 122, and two cylindrical chambers123 and 124 one at each end of the spool. The pipe 112 communicates withthe chamber 124 so that when compressed air is supplied through the pipe112 the spool 114 is displaced to the left in the FIG. 5 to its positionas shown.

A further pipe 126 communicates with the chamber 123, and whencompressed air is supplied through pipe 126 the spool 114 is displacedto the right in FIG. 5.

The pipe 126 communicates with one side of the air valve 37, the otherside of which is communicated with the compressed air source.

A port 130 in the casing 119 of the relay Valve 113 communicates at alltimes with the annular chamber 121,

and the port 130 communicates directly With the compressed air sourcethrough a pipe 131.

Two further ports 133 and 134 in the casing 119 communicate respectivelythrough pipes 135 and 136 with the upper and lower sides of the airmotor 28.

Ports 139 and 14-11 are also provided in the casing 119, the portscommunicating with atmosphere through adjustable needle valves 141 and142.

The air valves 26, 37 and 111) are of the lift valve type having pushrods to open the valves, the valves be ing normally held against theirseats by coiled compression springs.

When the plunger reaches the end of its withdrawal stroke the valvelifter 38 engages the push rod of the valve 21 and opens the valve 21The spool 114 of the relay valve 113 is at this time, as willhereinafter appear, displaced to the right in FIG. 5.

As soon as a carton blank has been positioned over the die aperture, theoperator operates the manual valve to open the valve and, inconsequence, compressed air is supplied, from the compressed air source,through the pipe 111, the valve 20 and the pipe 112 to the chamher 124to displace the spool 114 to the left in FIG. 5 to its position asshown, the air from the chamber 123 escaping past the land and throughthe chamber 120, the port 139 and the needle valve 141 to atmosphere.

The port 133 is then communicated with the annular chamber 121 and theport 134 with the annular cham her 122 which in turn communicates withatmosphere through the port 140 and the needle valve 142.

Compressed air accordingly passes from the chamber 121 through the port133 and the pipe to the top of the motor 28 and the motor is operated tomove the plunger through its advancing stroke, the air from the lowerside of the motor exhausting through the pipe 136, the port 134, theannular chamber 122, the port and the needle valve 142. As the plungeradvances the valve lifter 38 moves downwardly thus allowing the valve 20to close.

When the plunger reaches the end of its advancing stroke, the valvelifter 39 engages a push rod 152. which opens the valve 37. Compressedair then flows from the compressed air source through the valve 37 andthe pipe 126 to the chamber 123 and the spool 114 is displaced to theright in FIG. 5, the air from the chamber 124 escaping past the land118, chamber 122, the port 140 and through the needle valve 142 toatmosphere,

The port 134 is then communicated with the chamber 121 and the port 133with the chamber 1211 which in turn communicates with atmosphere throughthe port 139 and the needle valve 141.

Compressed air accordingly passes from the chamber 1'21 through the port134 and the pipe 136 to the lower side of the motor 28, and the motor isoperated to move the plunger through its withdrawal stroke, the upperside of the motor exhausting through the pipe 135, the port 133, thechamber 120, the port 139 and the needle valve 141.

As the plunger withdraws, the valve lifter 39 moves upwardly and thevalve 37 is allowed to close.

At the termination of the withdrawal stroke the valve 20 is againopened, but the spool 114 is not displaced again until such time as themanual valve 111} is operated.

Once the manual valve 110 is operated, to displace the the spool 114 asdescribed, the operation of the air motor continues until the plungeragain returns to its upper position reopening the valve 24}. It isensured therefore that once a carton erecting movement of the plunger isinitiated by the operator it cannot be interrupted until the cycle ofoperations has been completed.

However fast the operator works the machine therefore it cannot becomejammed with improperly formed cartons.

By adjusting the needle valves 141, 142 to restrict the exhaust of themotor the rate of operation of the motor may 'be adjusted.

The die 51 may be readily removed from the machine by unscrewing thescrews 55, slackening the tensioner 99, removing the chains, andunbolting the straps 95 and 98 whereafter the die may he slid outcomplete with the spindles 90 the sprocket wheels 94 and the strap 95.

A further die of a dilferent size may then be inserted and the plungerblock also exchanged. If the further die is to erect roll-over end orside lock cartons, the further die would have its own strap 95, andconveniently although not necessarily its own sprocket Wheels 94, thechain drives being reconnected or substituted by chains of appropriatelength to suit the new die.

When connecting the chains to the sprocket wheels of the new die it isnecessary to ensure that the fingers 93 are in their fully operativeposition folding the rollover panels when the assembly 21 is at the topof its withdrawal stroke. The operation of the fingers 93 is thenproperly timed in relation to the movement of the plunger block.

Since this timing adjustment must be accurately per formed, the sprocketwheels 94 are splined to the spindles 90 so as to provide for fineangular adjustment of the sprockets on the spindles. In the presentexample the splines provide for an angular adjustment of one-fifth ofthe pitch angle of the sprocket teeth.

The splined connections between the sprocket wheels 94 also ensure thatthe timing cannot slip during operation of the machine.

The interchangeable dies may be of different depths provided only thatthe die frames 51a are so located in relation to the upper surface ofthe die that when the die is slid into the machine frame the uppersurface is level with the surface of the feed-in tray.

If a die of different depth is substituted it is necessary also toadjust the stroke of the plunger. This may be done by interchanging thesleeves 33a. It is also necessary to ensure that the valve 37 isoperated only at the end of the shorter or longer advancing stroke. Thismay be done by adjusting the height of the valve lifter 39.

If the operation of valve 37 cannot be correctly adjusted Within therange of adjustment afforded by the valve lifter 39, the push rod 152which operates the valve 37 may be interchanged.

Referring to FIG. 1, the rod 152 is supported for sliding movement in apair of spaced eyes 1.51 attached to the back of the column 12, the rod152 resting on the push rod proper of the valve 37. A spring 154 on therod 152 engages between the lower eye and a transverse pin 153 in a borein the rod, the spring supporting the main part of the weight of therod.

By interchanging the rod 152 for a shorter or longer rod it may beensured that the valve 37 is opened only at the end of the shorter orlonger stroke required.

To interchange the rod all that is necessary to withdraw the spring pinand slide the rod out of the eyes 151, the new rod being mounted in theconverse manner.

It will be appreciated that since the fingers 93 are intermittentlyoperated, the stroke of the plunger may be altered, within limits,Without affecting the proper operation of the fingers.

The extent to which the stroke may be altered depends on the extent ofthe lost motion in the finger operating mechanism corresponding withthat period of the stroke during which the rollers 101 are running onthe rods 22.

By selecting the extent of this lost motion therefore the machine may bedesigned to operate with a required range of rams and dies entailing arange of strokes the longest to the shortest of which might differ by anamount approaching the extent of the lost motion referred to.

As previously mentioned the ram and die of the machine described may beinterchanged with a ram and die suitable for erecting a different styleof carton Le. a

8 carton not employing roll-over locks to hold it in its erectedcondition.

In this case no roll-over fingers 93 would be provided, and the chainsnormally driving the sprocket wheels 94 would be removed.

Although, in this case there is no need to disengage the trigger levers1%, these may be swung around so as no longer to be operated by the camblock 25. To this end holes or pins 150 are provided on the triggerlevers to which the timer ends of the springs may be attached, thesprings then holding the rollers 101 out of contact with thereciprocating assembly 21.

I claim:

1. A carton folding machine for converting carton blanks into cartonform, the machine comprising a frame, a plunger assembly reciprocable onthe frame through an advancing and a withdrawal stroke, the plungerassembly including a plunger block, a die supported on the frame of asize to receive the plunger block, the block being movable into the dieon the advancing stroke of the plunger assembly to upfold against thesides of the plunger block the side forming portions of a carton blankforced into the die by the block and thereby partly form the carton,means in the die for engaging the partly formed carton when the plungerassembly reaches the end of its advancing stroke so that on thewithdrawal stroke of the plunger assembly the partly formed carton isstripped off the plunger block and supported in the die aperture,folding means in the die, movable between a retracted and an operativeposition, for folding inwardly into the stripped, partly formed cartoninto locking position a lock panel of the carton, and intermittentmovement transmission means operatively inter-connecting the pulngerassembly and the folding means intermittently to transmit movement fromsaid plunger assembly to said folding means to move said folding meansfrom its retracted to its operative position to fold the locking panelinto its locking position while the plunger assembly is moved through apart only of its withdrawal stroke, and to move said folding means fromits operative position to its retracted position while the plungerassembly is moved through a corresponding part of its advancing stroke.

2. A carton folding machine for converting carton blanks into cartonform, the machine comprising a frame, a plunger assembly reciprocable onthe frame through an advancing and a withdrawal stroke, the plungerassembly including a plunger block, a die supported on the frame of asize to receive the plunger block, the block being movable into the dieon the advancing stroke of the plunger assembly to upfold against thesides of the plunger block the side forming portions of a carton blankforced into the die by the block and thereby partly form the carton,means in the die for engaging the partly formed carton when the plungerassembly reaches the end of its advancing stroke so that on thewithdrawal stroke of the plunger assembly the partly formed carton isstripped off the plunger block and supported in the die aperture,folding means in the die, movable between a retracted and an operativeposition, for folding inwardly into the stripped, partly formed cartoninto locking position a lock panel of the carton, and intermittentmovement transmission means operatively inter-connecting the plungerassembly and the folding means intermittently to transmit movement fromsaid plunger assembly to said folding means to move said folding meansfrom its retracted to its operative position to fold the locking panelinto its locking position while the plunger assembly is moved through aterminal part of its withdrawal stroke, and to move said folding meansfrom its operative position to its retracted position while the plungerassembly is moved through a corresponding, initial part of its advancingstroke.

3. A machine as claimed in claim 2, wherein said intermittent movementtransmission means comprises inter- 3,oss,sss

acting cam and cam follower means one on the frame and the other on theplunger assembly.

4. A machine as claimed in claim 3, wherein the cam means is on theplunger assembly, and the cam follower means is a lever pivoted on theframe and connected to move said foldin means, the lever carrying aroller and spring means being provided pressing said roller intoengagement with the cam means, the cam means moving the roller angularlyto adjust the lever to impart the intermittent movement to the foldingmeans.

5. A machine as claimed in claim 4, comprising a stepup gearing drivablyconnecting the lever to the folding means.

6. A carton folding machine for converting carton blanks into cartonform, the machine comprising a frame, a plunger assembly reciprocable onthe frame through an advancing stroke and a withdrawal stroke, theplunger assembly including an interchangeable plunger block removablyattached to the assembly, an interchangeable die removably supported onthe frame of a size to receive the plunger block, the plunger blockbeing movable into the die on the advancing stroke of the plungerassembly to upfold against the sides of the plunger block the sideforming portions of a carton blank forced into the die by the plungerblock and thereby partly form the carton, means in the die for engagingthe partly formed carton when the plunger assembly reaches the end ofits advancing stroke so that on the Withdrawal stroke of the plungerassembly the partly formed carton is stripped off the plunger block andsupported in the die aperture, folding means in the die, movable betweena retracted and an operative position, for folding inwardly into thestripped, partly formed carton into locking position a lock panel of thecarton, and intermittent movement transmission means operativelyinter-connecting the plunger assembly and the folding meansintermittently to transmit move ment from said plunger assembly to saidfolding means to move said folding means from its retracted to itsoperative position to fold the locking panel into its looking positionwhile the plunger assembly is moved through a part only of itswithdrawal stroke, and to move said folding means from its operativeposition to its retracted position while the plunger assembly is movedthrough a corresponding part of its advancing stroke.

7. A carton folding machine as claimed in claim 6, wherein the die issupported on horizontal runner on said frame and means is providedlocating the die on said runners in line with the plunger block.

8. A carton folding machine for converting carton blanks into cartonform, the machine comprising a frame, a plunger assembly reciprocable onthe frame through an advancing stroke and a withdrawal stroke, theplunger assembly including an interchangeable plunger block removablyattached to the assembly, an interchangeable die removably supported onthe frame of a size to receive the plunger block, the plunger blockbeing movable into.

the die on the advancing stroke of the plunger assembly to upfoldagainst the sides of the plunger block the side forming portions of acarton blank forced into the die by the plunger block and thereby partlyform the carton, stripping means in the die for engaging over the partlyformed carton when the plunger assembly reaches the end of its advancingstroke so that on the withdrawal stroke of the plunger assembly thepartly formed carton is stripped off the plunger block folding means inthe die, movable between a retracted and an operative position, forfolding inwardly into the stripped, partly formed carton into lockingposition a lock panel of the carton, and intermittent movementtransmission means operatively interconnecting the plunger assembly andthe folding means intermittently to transmit movement from said plungerassembly to said folding means to move said folding means from itsretracted to its operative position to fold the locking panel into itslocking position while the plunger assembly is moved through a part onlyof its withdrawal stroke, and to move said folding means from itsoperative position to its retracted position while the plunger assemblyis moved through a corresponding part of its advancing stroke, andinterchangeable stop means on the frame for limiting the advancingstroke of the plunger assembly whereby said stripping means engages overthe partly formed carton when the plunger assembly reaches the end ofits advancing stroke.

9. A carton folding machine for converting carton blanks into cartonform, the machine comprising a frame, a plunger assembly reciprocable onthe frame through an advancing stroke and a withdrawal stroke, theplunger assembly including a plunger block, a pneumatic motor on theframe and connected with said plunger assembly, said motor beingoperable to move the plunger assembly at least through its advancingstroke, a die supported on the frame of a size to receive the plungerblock, the plunger block being movable into the die on the advancingstroke of the plunger assembly at least partly to form a carton blankforced into the die by the plunger block, a relay valve connected withsaid motor and actuable to supply compressed air to said motor tooperate the motor to move the plunger assembly through its advancingstroke, first switch means on said frame and operable by the plungerassembly when it reaches the end of its withdrawal stroke, said firstswitch means being operatively conected with said relay valve, andmanual switch means connected in series with said first switch means andoperable when said first switch means is operated to actuate said relayvalve.

10. A carton folding machine for converting carton blanks into cartonform, the machine comprising a frame, a plunger assembly reciprocable onthe frame through an advancing stroke and a withdrawal stroke, theplunger assembly including a plunger block, a double acting pneumaticmotor on said frame and connected with said plunger assembly, said motorbeing operable in one direction to move said plunger assembly throughits advancing stroke and in the other direction to move said plungerassembly through its withdrawal stroke, a die supported on the frame ofa size to receive the plunger block, the plunger block being movableinto the die on the advancing stroke of the plunger assembly at leastpartly to form a carton blank forced into the die by the plunger block,a relay valve connected with said motor, said relay valve beingselectively actuable to supply compressed air to said motor to operatethe motor and move said plunger assembly through its advancing strokeand its withdrawal stroke, first switch means on said frame and operableby the plunger assembly when it reaches the end of its withdrawalstroke, second switch means on said frame and operable by the plungerassembly when it reaches the end of its advancing stroke, said first andsecond switch means being operatively connected with said relay valve,said second switch means, when operated, to actuate said relay valve tooperate said motor to move the plunger assembly through its withdrawalstroke, and manual switch means connected in series with said firstswitch means and operable when said first switch means is operated toactuate said relay valve to operate said motor to move the plungerassembly through its advancing stroke.

11. A carton folding machine for converting carton blanks into cartonform, the machine comprising a frame, a plunger assembly reciprocable onthe frame through an advancing stroke and a withdrawal stroke, theplunger assembly including a plunger block, a double acting pneumaticmotor on said frame and connected with said plunger assembly, said motorhaving a first compressed air port through which compressed air may besupplied to operate the motor in one direction to move said plungerassembly through its advancing stroke, and a second compressed air por-tthrough which compressed air may be supplied to operate the motor in theother direction to move said plunger assembly through its withdrawalstroke, a die supported on the frame of a size to receive the plungerblock, the plunger block being movable into the die on aoaasas 1, ll theadvancing stroke of the plunger assembly at least partly to form acarton blank forced into the die by the plunger block, a relay valveconnected with both said compressed air ports, said relay valve beingselectively actuable to supply compressed air to either one of saidports and communicate the other of said ports with atmosphere, firstswitch means on said frame and operable by the plunger assembly when itreaches the end of its withdrawal stroke, second switch means on saidframe and operable by the plunger assembly when it reaches the end ofits advancing stroke, said first and second switch means beingoperatively connected with said relay valve, said second switch means,when operated, to actuate said relay valve to supply compressed air tosaid second compressed air port and to connect said first compressed airport to atmosphere, and manual switch means connected in series withsaid first switch means and operable when said first switch means isoperated to actuate said relay valve to supply compressed air to saidfirst compressed air port and 112 to connect said second compressed airport to atmosphere.

12. A machine as claimed in claim 11, wherein said relay valve connectssaid compressed air ports to atmosphere each through an adjustablerestriction.

13. A machine as claimed in claim 11, wherein said first and secondswitch means and said manual switch means are air valves, and said relayis compressed air actuated.

References Cited in the file of this patent UNITED STATES PATENTS2,743,651 Wilcox May 1, 1956 2,819,660 Johnson Jan. 14, 1958 2,830,507Hickin et al Apr. 15, 1958 2,837,014 Burke June 3, 1958 2,848,926Gschwind et -al Aug. 26, 1958 2,921,506 Johnson Jan. 19, 1960

